Thursday, June 9, 2011

Why I became a nuclear engineer

In celebration of the fact that I will be conducting my final defense for my doctorate in nuclear engineering next Friday, I wanted to change gears a little bit and take on a bit more of a personal subject. Namely, I'd like to talk a little bit more about why I chose to go into nuclear engineering in the first place.

Nuclear advocates like Suzy Hobbes and the Nuclear Literacy Project have spoken about the need to put a human face to nuclear engineering. My own hope here is to perhaps inspire a conversation among many nuclear professionals, each of whom have had their own path into nuclear energy, as both engineers and advocates. I'll follow up on this post with links to others' responses as they roll in.

In the beginning...

Unlike many whose views on energy were shaped by the Oil Crisis of the 1970s, I was born much later (well, perhaps not that much later). Late enough at least that the specter of large-scale energy shortages seemed like distant history to me growing up. Nor did I take the path of many who came into nuclear engineering through the nuclear navy (although I did consider the option at the time). In that sense, you might say that my experience is perhaps more representative of the newer generation of nuclear professionals entering the workforce, those born in the 1980's (like me) and 1990's.

For me growing up, nuclear energy always seemed like a bit of an underdog, having been born between the time of Three Mile Island and Chernobyl. Nuclear technology held untapped promise of plentiful energy whose time essentially came and went. I grew up in the time where nuclear power plants were a lot like classic cars: beautiful to behold, but they just don't make 'em anymore. (Incidentally, where I grew up received about 20% of its power from the now currently-famous Fort Calhoun nuclear plant). The 90's were generally a time where nuclear energy was viewed as being on the downward slope: not a single new plant had been built in the U.S. since I had been born while enrollment in university nuclear engineering programs was in a slow decline.

Suffice it to say, a career in nuclear energy didn't exactly seem like a viable career option at the time. This began to change just around the time I started my undergraduate years, but the "Nuclear Renaissance" was still well-off in the horizon at that point.

"Nuclear power is great, but..."

Meanwhile, nuclear power, when not associated with the bumbling Homer Simpson or the barely-operational Springfield Nuclear Power Plant, it was spoken of in terms of the ultimate intractability: how to deal with spent fuel waste. In other words, "Nuclear energy is great, but what do we do about the waste?" It is perhaps the most prevalent question many of us encounter even still today.

Among my friends and colleagues in physics, nuclear energy was generally viewed in very favorable terms - lovable but misunderstood. It was a working assumption that nuclear power was safe - this was science after all, and science we'd done half a century ago (even if the public didn't get this). Yet even our conversations turned inevitably to, "But what do you do about the waste?" Being physicists, we appreciated quite well the long-term nature of the half-lives of actinides in spent fuel (such as plutonium, neptunium, and americium). And of course, being physicists, we had all kinds of crazy solutions.

"Well, couldn't we just blast it into the Sun?"
"What if we buried it a deep ocean trench?"
"How about we ship it to Antarctica?"

Needless to say, I was actually a little shocked when these options actually came back up once I was taking a waste management class as options which were considered but otherwise seen as impractical. (Namely I was shocked because these were ideas being tossed around by smart people who otherwise knew very little about nuclear engineering overall - we just liked the idea of a thought problem.)

It wasn't until much later that I would by chance read an article in Scientific American talking about the untapped energy potential in nuclear fuel, and in particular how much of what we consider "waste" is in fact a recoverable resource. By mass, about 97% of "spent" nuclear fuel is recoverable - and with these recoverable elements taken out, the bulk of the toxic radioactivity is gone after around 300 years, rather than over millions of years.

At that point, the potential for nuclear energy seemed blatantly obvious to me, having that issue solved. I began to become a more passionate advocate; my greatest frustration overall was simply, "Why are we not taking advantage of this?" But even still, the business of building and operating nuclear power units was for someone else - I was still a physicist, after all.

"Very interesting. So how does that help people?"

Going forward a few years to when I was finishing my master's degree in Nuclear Physics. It was the mid 2000's by this point (so you can probably guess my age by now). I was happily at work involved with an experiment at the Relativistic Heavy Ion Collider (RHIC), looking into collisions of heavy particles to try and unravel some of the secrets of what fundamentally makes up atoms at the sub-atomic level, and ultimately where all matter in our universe came from.

This of course was pure science at its best: deep mystery, fundamental questions, and absolutely zero immediately foreseeable practical applications. It was first and foremost simply about satisfying a deep curiosity. And of the wonders of this work, I was a tireless evangelist, trying to impress upon anyone and everyone I could about the deep wonder about the mysteries we were unfolding. (This would include even the woman who would become my wife - the very fact that she tolerated my rambling about this research during our first date and actually agreed to go on a second indicated she was a keeper...)

Around that time, I was spending a holiday with my extended family nearby, proselytizing about the wonder and mysteries we were investigating. One of my older cousins listened with polite attention, and when I was finished, he asked me, "That all sounds very interesting. So how does it help people?"

At the time, I gave a rambling and not very convincing answer about how science leads us to unexpected developments. It was of course true, in a sense - for example, much of what we consider a mundane part of our modern lives now trace their existence back to the development of quantum mechanics; specifically, anything involving a semiconductor (which of course includes computers, cell phones, and all other forms of digital electronics).

The question lay dormant in me for a long time, however, festering every now and then. I couldn't help but think that I wanted to do something with my career to make a positive difference in the world. And while scientific discovery was both interesting and fulfilling, how it "helped" people was mostly a vague abstraction.

When I was a young child, my first ambition (before wanting to be a physicist) was to be an inventor - namely so I could help to invent things that would one day truly help create a better world. My ideas were ultimately not that great (although who can really blame an eight-year old for that?), but the fundamental motivation was still there.

From physicist to educator...

I left graduate school and went in a different direction for awhile, becoming a science educator at a museum in Chicago. My thought was that perhaps I could use my love of science and teaching to reach out to people and show them some of the wonders of the world, even perhaps to help inspire the next generation of scientists and engineers. My sense of childlike wonder was still quite infectious - it was truly easy, a joy even, for me to find the energy and enthusiasm to explain just how awe-inspiring the universe around us is and how we are just beginning to understand it. I loved teaching; I truly enjoyed being a teaching assistant in graduate school and I loved teaching anyone who would listen (especially children) about the wonders all around us in the universe.

...to engineer...

One thing that struck me while I working as an educator was a series of lectures by climate scientists being held at the museum (particularly with the focus of how satellites were just beginning to paint a picture of climate change). I'd never really been one to doubt the idea of anthropogenic climate change in general (the basic physics, after all, seemed dead simple to a physicist or anyone who'd spent time with a hot car in summer); only the degree of which was ever really in dispute for me.

At this point, the severity of the issue began to seem inescapable to me. I was first and foremost a scientist, and perhaps still a bit of an inventor - what was I doing about this? How would I help?

(To make bit of an aside here - my politics and personality don't exactly make me the stereotypical environmentalist and/or sandal-wearing hippie. Throw out the term "organic" and I'm as likely to roll my eyes; mention "alternative medicine" and I'll likely start to grumble about hippie nonsense. But it's hard not to look at what appears to be fairly obvious science when it comes to climate change and not be just a little worried.)

I remember looking over Lake Michigan at the Chicago skyline at night, seeing a glimmering monument to the abundance and progress that plentiful energy had brought us. At that point, it seemed obvious: the only way we'd ever be able to seriously confront the issue of carbon emissions while continuing to maintain anything close to our level of prosperity was to begin to seriously embrace nuclear energy in earnest. Nothing else could provide both the abundant level of energy that our economic prosperity has come to depend upon while staving off an eventual ecological catastrophe. Even then, I was skeptical of wind energy (the availability and energy density alone made it seem impractical), solar seemed like a distant pipe dream, and so-called "clean coal" an absolute lie. And the alternative - essentially asking people to live in caves, eschewing modernity altogether - was unthinkable.

By that time, I had a voracious interest in the Generation-IV nuclear designs then being touted - concepts like the Very High Temperature Reactor (VHTR), which could produce energy at much higher efficiencies and even perhaps be used for process heat in other applications like hydrogen (remember the "hydrogen economy?") or the pebble-bed reactor, which promised the ultimate level of safety. Nuclear technology was actually something new and exciting to me once more - and I wanted to be one of its pioneers.

And so with that I threw the dice - leaving a stable job for a complete risk, going back to grad school and not knowing what the future might hold

...to nuclear researcher

Of course, in my wild enthusiasm, what I perhaps would overlook was the fact that despite the fact that the Nuclear Renaissance was in bloom, we still weren't exactly building that many new reactors, and Gen-IV reactors were a decade or more away from even being remotely commercial concepts. And of course, like many kinds of "sexy" science, I'd also overlook the fact that the real beginning "design" work was already done; they didn't need people to design Gen-IV reactors, they needed people to run simulations on aspects like how neutrons are created and absorbed, as well as "thermal hydraulics" (i.e., where heat is created in the reactor and where it goes). Having absolutely no background in nuclear engineering, it was a task I wasn't even remotely qualified for at the time (despite my training as a physicist). It also lacked some of the urgency that I (rather naively) came in with.

It was perhaps a twist of fate that the director of graduate programs at the time I interviewed at NC State would be the person who would later become my adviser; or, incidentally, the reason I was admitted to NC State to begin with. (My undergraduate academic record he described dismally as, "not very impressive," but he took great notice of my passion; it was ultimately this, and the potential for research that he saw in me, that lead to his decision to recommend my admission.)

My adviser is perhaps a bit of an outlier in terms of personality, much like me. Beyond the simple technical challenge, at his core he is someone who is driven by ethical concerns - especially in terms of how we can make a better world, leading him into nuclear engineering, and particularly his focus, which focuses more upon what one might call the "social" issues of engineering, such as public perception of risk, nonproliferation and safeguards, and nuclear waste management. I realized working with him that there still were challenges to be solved, with the potential to do enormous good in the world.

This is where I would develop a passion for challenges like how we can close the nuclear fuel cycle by recovering the long-lived elements in spent fuel, rather than throwing it all away intact. This as well struck me as the place where I might be able to make a real positive difference, helping to finally clear the path of the last barriers to the much broader deployment of nuclear energy.

Even now, in my view, the issue of nuclear waste management is the last true barrier to widespread public acceptance of nuclear energy. Despite everything that has occurred with Fukushima, I believe that the reactors we have now and more importantly, the reactors we will build, are fundamentally safe, and will continue to get safer with the advance of technology and experience. Thus, it is not fundamentally an issue of safety that stands in the way of nuclear energy development, but a public understanding that we have a plan for spent fuel beyond simply dumping it all into a (very well-studied) hole in the ground and hoping for Mother Nature to do her best. (Please don't mistake me - I think Yucca Mountain was by all accounts technically sound - just also a tremendous waste.)

Of course, what I know now is that closing the nuclear fuel cycle is also not strictly a technical problem - it is one with a wide array of social, political, and economic challenges. But some of these problems too can be attacked via technical means - namely by investigating ways to make reprocessing cheaper and easier and developing solutions to allow us to guard against its potential misuse.

In that sense, so many years later now, I can finally answer my relative's question with a much greater degree of confidence. It's why I'm passionate about what I do - because from my perspective, this is what I can do to leave a better world for my children and their children. And I'm sure I'm not the only nuclear engineer who thinks this way.

So it's with some excitement that I look forward beyond next week, to the point where I truly begin my career as a nuclear engineer... and scientist.